Minor bleeds with VKAs should alert physicians to major bleed risk
MedWire News: Minor bleeds may increase the risk for a subsequent major bleed by three-fold among patients taking vitamin K antagonists (VKA), study findings indicate.
"This increased risk was independent of the amount of over-anticoagulation," report Nic Veeger (University Medical Centre Groningen, The Netherlands) and colleagues in the British Journal of Haematology.
"VKAs are effective in primary and secondary prevention of thromboembolism, but the associated risk of bleeding is an important limitation," say the researchers.
They add that although the majority of bleeds are clinically mild, the occurrence of a minor bleed during VKA therapy could indicate an increased risk for a major bleed in future.
To investigate whether this is the case, Veeger and team retrospectively reviewed data for 5898 patients who received VKA treatment, predominantly (97%) with acencoumarol, for a median period of 9 months.
A total of 1501 minor bleeds occurred in 1015 (17%) patients to give an incidence rate of 29.6 cases per 100 person-years. The most common types of minors bleeds included hematomas (40%), nose bleeds (27%), conjunctiva bleeds (11%), and hematuria (10%).
Major bleeding (gastrointestinal, intracranial, intra-ocular) occurred in 56 (0.9%) patients, with an incidence rate of 1.4 per 100 person-years.
The researchers report that the incidence of major bleeds was significantly higher among patients who had previously suffered a minor bleed relative to those who had not, at 2.3 versus 1.2 cases per 100 person-years.
Indeed, a minor bleed was associated with a 2.9-fold increased risk for major bleeding during the following month, compared with no minor bleeding, independent of other risk factors such as over-anticoagulation (defined as more than 9% of treatment time above an International Normalized Ratio of 5.0), diabetes, cancer, diuretic use, and age above 70 years.
"The occurrence of a minor bleed should increase the awareness towards a potentially high-risk situation," Veeger et al remark.
They speculate that a "lower intensity of anticoagulation might be more suitable for these high-risk patients, without compromising the efficacy of VKA therapy to prevent thromboembolic complications."
"For some patients, no anticoagulant agent, aspirin, or - in the near future - an oral [factor] II or Xa inhibitor might be a more suitable option," they add.
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By Laura Dean